@UrbanTracker One its a motion tracker not a heartbeat sensor, don't ruin these films, and Two I don't think heartbeat sensors exist in real life...can you imagine how unbelievably accurate they would have to be, heart monitors are pretty big in hospitals, and that is just for one heartbeat, so I doubt you could attach it to a gun, plus even if they did there would be so much interference it probably wouldn't work unless you were on, say I dunno...the moon, plus I hate to tell you but MW2 is based on real events, sorry.
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